Albumin recovery with centrifugal adsorption technology (CAT)

Centrifugal adsorption technology (CAT) is a new compact, countercurrent technology for efficient adsorption from large liquid streams by using adsorbent particles in the micrometer range. CAT seems particularly suited for the recovery of macromolecules at low concentrations, because the small particle dimensions lead to fast mass transfer rates. In this work, the potential of CAT for protein recovery is studied by model and experiment. A predictive model for the separation performance of CAT is presented, incorporating mass transfer resistance and axial dispersion transport in the liquid and the adsorbent phases. The model calculations were compared to experimental data for the adsorption of bovine serum albumin (BSA) on a standard commercial anion-exchange resin with particle diameter d(p) = 50 microm in a pilot-scale CAT apparatus. The model calculations accurately predicted the separation efficiency of CAT. The experimental set-up is shown to be mass transfer limited for the conducted experiments, which agrees with the model predictions. The model was also used to estimate the dimensions and performance of a CAT apparatus for the large-scale recovery of human serum albumin (HSA) from fermentation broth at the scale of 40 tons per year. The resulting equipment dimensions proved to be very small indeed, making CAT a potentially very attractive technology.